1. Field of the Invention
This invention relates to the management of a plurality of IP-based devices such as IP-based KVM (IKVM) switches, and in particular, it relates to the management of IP-based devices located on different subnets in a consolidated manner.
2. Description of the Related Art
A KVM (keyboard, video, mouse) switch is a device that connects multiple computers to one or more user consoles. Each user console typically includes a monitor and a set of user input devices such as a keyboard and a mouse. Each user console can selectively communicate with one or more of the computers connected to the KVM switch. An IKVM switch (sometimes referred to as IP-based KVM, or KVM over IP, or more generally, network-based KVM) is a KVM switch that can be accessed via a network such as the Internet, a WAN (wide area network), a LAN (local area network), etc. In an IKVM system, a user console is typically connected to a client computer which is connected to the network. The computers connected to the IKVM switch are referred to as the remote computers as they are located remotely from the client computer.
FIG. 1 schematically illustrates a conventional IKVM system comprising a plurality of IKVM switches. In this system, a plurality of control computers (referred to as control centers in this disclosure) 130, 230, 330 are connected to a network 100 such as the Internet, a WAN, etc., via a plurality of respective routers 120, 220, 320. A group of one or more IKVM switches 141, 142 (or 241, 242, or 341, 342) are connected to each router 120 (or 220, or 320, respectively). Each IKVM switch 141, (or 142, 241, . . . ) is connected to a plurality of computers (referred to as remote computers) 151, 152 (or 153, 154, 251-254, 351-354). In FIG. 1, to avoid overcrowding, only two IKVM switches are shown for each control center, and only two computers are shown for each IKVM switch. A client 10 is connected to the network 100, and includes a client computer 10a and a user console 11 including a monitor 11a and user input devices such as a keyboard 11b and/or a mouse 11c. In FIG. 1, the control centers 130, 230, etc. and the client 10 are all shown as connected to an open network 100 such as the Internet. Alternatively, the control centers 130, 230, etc. may be connected to a private WAN, while the client 10 accesses one or more of the control centers via the Internet.
Each IKVM switch 141, etc. has a switching function to allow the client 10 to communicate with and control any selected one of the remote computers connected to that IKVM switch. Specifically, the IKVM switch transmits video data from the selected remote computer to the client 10 via the network 100, and transmits keyboard and mouse data received from the client 10 over the network to the selected remote computer.
Each control center 130 (or 230, or 330) manages the respective one or more IKVM switch devices 141, 142 (or 241, 242, or 341, 342, respectively) connected to the corresponding router 120 (or 220, or 320). The assignee of the present invention, Aten International Co., Ltd., manufactured a software product, referred to as “CC1000”, which can be installed on the control centers 130 etc. in the conventional IKVM system shown in FIG. 1. The control center 130, etc. running the CC1000 software manages the devices 141, etc. attached to it, including regulating user access to the attached devices (i.e. providing security control), providing a web browser-based user interface to allow access to attached devices over the network, etc. Each IKVM switch devices 141, etc. managed by a control center runs a software program to enable them to cooperate with the control center.
In the system of FIG. 1, the devices that are connected to each router (i.e. a control computer and multiple IKVM switches) form a local network (a subnet), and the respective router connects the subnet to the network 100. In a typical situation, each subnet is a private network and the devices on the subnet cannot be accessed from the outside directly.
In the conventional IKVM system of FIG. 1, the client 10 can only access an IKVM switch (and the remote computer connected to that IKVM switch) by logging on to the control center connected to the same router as the IKVM switch. For example, to access the IKVM switch 141 and the remote computer 151, the client 10 must log on to the control center 130.